Scanning electron microscopy (SEM) uses a focussed electron beam to image the surface of a material. The focussed electrons cause the emission of secondary electrons, and by scanning the beam across the surface of the sample, a spatial image of surface morphology is generated as a function of this secondary electron intensity. Image resolution to 1 nm can be achieved under optimal conditions, and magnification to 500000 times is possible. Some SEM systems can also take advantage of back scattered electrons (BSE) and x-ray emission generated by the probe beam to perform material composition analysis.
The CEDT operates an Hitachi S-2150 SEM. The system is suitable for scans to sub-micron resolution.